The reason i had to believe it came from Waterloo in the first place was that there are quite a lot a memorabilia from it. I did not know the Crimean war also had the same phenomenon.

When it come to journalists, due to my experience in former Yugoslavia i know that they like to show things according a certain "angle".

I am glad for what I could add here, and while the display apparently was not from Waterloo as you had hoped, the Crimean War was also rich in historical context. For me personally it was exciting to revisit the extensive research I enjoyed on both over many years. The memorabilia phenomenon is of course pretty universal in the human experience as nostalgia and curiosity effects most people in one way or another.

I thank you for sharing this item here, and giving us a chance to learn from it.

I would add that it seems a number of these 'arrangements' of ordnance from Crimean War context appear to be 'marketed' online with similar setup and brass plaques.
Perhaps these might imitate earlier such displays of actual souvenirs from the Crimea which became prototypes for these 'marketed' arrangements.

An interesting instance found under "War Tourism" (Wiki):
"...during the Crimean War, tourists led by Mark Twain visited the wrecked city of Sevastopol- he even scolded his travel mates for walking off with SOUVENIR SHRAPNEL".

It would seem that while there MAY have been authentic such displays of such materials in those times.....obviously as with all manner of militaria and these kinds of items, one must be aware of the constant presence of modern creations of same.

There is no harm in optimism in observing items shown, however all possibilities must be considered equally. Discussing an item toward its inherent historical potential whether authentic or not is not necessarily the concern of the discussion, for some of us it is the history being represented that is important.
To each his own, and for collectors, as always.....caveat emptor.